Moduł:Bit
n) bit.bxor(m, n) -- bitwise xor (m ^ n) bit.brshift(n, bits) -- right shift (n >> bits) bit.blshift(n, bits) -- left shift (n << bits) bit.blogic_rshift(n, bits) -- logic right shift(zero fill >>>) Please note that bit.brshift and bit.blshift only support number within 32 bits. 2 utility functions are provided too: bit.tobits(n) -- convert n into a bit table(which is a 1/0 sequence) -- high bits first bit.tonumb(bit_tbl) -- convert a bit table into a number ------------------- Under the MIT license. copyright(c) 2006~2007 hanzhao (abrash_han@hotmail.com) 2013-02-20: Brad Jorsch: Fix to not try messing with globals, doesn't work in Scribunto ----------------- do ------------------------ -- bit lib implementions local function check_int(n) -- checking not float if(n - math.floor(n) > 0) then error("trying to use bitwise operation on non-integer!") end end local function to_bits(n) check_int(n) if(n < 0) then -- negative return to_bits(bit.bnot(math.abs(n)) + 1) end -- to bits table local tbl = {} local cnt = 1 while (n > 0) do local last = math.mod(n,2) if(last 1) then tblcnt = 1 else tblcnt = 0 end n = (n-last)/2 cnt = cnt + 1 end return tbl end local function tbl_to_number(tbl) local n = table.getn(tbl) local rslt = 0 local power = 1 for i = 1, n do rslt = rslt + tbli*power power = power*2 end return rslt end local function expand(tbl_m, tbl_n) local big = {} local small = {} if(table.getn(tbl_m) > table.getn(tbl_n)) then big = tbl_m small = tbl_n else big = tbl_n small = tbl_m end -- expand small for i = table.getn(small) + 1, table.getn(big) do smalli = 0 end end local function bit_or(m, n) local tbl_m = to_bits(m) local tbl_n = to_bits(n) expand(tbl_m, tbl_n) local tbl = {} local rslt = math.max(table.getn(tbl_m), table.getn(tbl_n)) for i = 1, rslt do if(tbl_mi 0 and tbl_ni 0) then tbli = 0 else tbli = 1 end end return tbl_to_number(tbl) end local function bit_and(m, n) local tbl_m = to_bits(m) local tbl_n = to_bits(n) expand(tbl_m, tbl_n) local tbl = {} local rslt = math.max(table.getn(tbl_m), table.getn(tbl_n)) for i = 1, rslt do if(tbl_mi 0 or tbl_ni 0) then tbli = 0 else tbli = 1 end end return tbl_to_number(tbl) end local function bit_not(n) local tbl = to_bits(n) local size = math.max(table.getn(tbl), 32) for i = 1, size do if(tbli 1) then tbli = 0 else tbli = 1 end end return tbl_to_number(tbl) end local function bit_xor(m, n) local tbl_m = to_bits(m) local tbl_n = to_bits(n) expand(tbl_m, tbl_n) local tbl = {} local rslt = math.max(table.getn(tbl_m), table.getn(tbl_n)) for i = 1, rslt do if(tbl_mi ~= tbl_ni) then tbli = 1 else tbli = 0 end end --table.foreach(tbl, print) return tbl_to_number(tbl) end local function bit_rshift(n, bits) check_int(n) local high_bit = 0 if(n < 0) then -- negative n = bit_not(math.abs(n)) + 1 high_bit = 2147483648 -- 0x80000000 end for i=1, bits do n = n/2 n = bit_or(math.floor(n), high_bit) end return math.floor(n) end -- logic rightshift assures zero filling shift local function bit_logic_rshift(n, bits) check_int(n) if(n < 0) then -- negative n = bit_not(math.abs(n)) + 1 end for i=1, bits do n = n/2 end return math.floor(n) end local function bit_lshift(n, bits) check_int(n) if(n < 0) then -- negative n = bit_not(math.abs(n)) + 1 end for i=1, bits do n = n*2 end return bit_and(n, 4294967295) -- 0xFFFFFFFF end local function bit_xor2(m, n) local rhs = bit_or(bit_not(m), bit_not(n)) local lhs = bit_or(m, n) local rslt = bit_and(lhs, rhs) return rslt end -------------------- -- bit lib interface local bit = { -- bit operations bnot = bit_not, band = bit_and, bor = bit_or, bxor = bit_xor, brshift = bit_rshift, blshift = bit_lshift, bxor2 = bit_xor2, blogic_rshift = bit_logic_rshift, -- utility func tobits = to_bits, tonumb = tbl_to_number, } return bit end -- for i = 1, 100 do for j = 1, 100 do if(bit.bxor(i, j) ~= bit.bxor2(i, j)) then error("bit.xor failed.") end end end --